1. Technical Field
The present invention relates to an electric driving machine which uses a motor as a driving drive source for driving a fastener, such as nails, staples, and the like. The present invention relates particularly to an electric driving machine including a power transmission mechanism—which has a clutch mechanism for transmitting rotational drive force of a motor in the electric driving machine, as rectilinear drive force, to an actuator having a drive blade for driving the fastener—and a controller for controlling operation timing of the motor.
2. Description of the Related Art
A pneumatic driving machine—which guides air compressed by an air compressor through use of an air hose and uses the thus-guided air as a power source—is most frequently utilized as a system for driving a common, related-art fastener driving machine, because the driving machine is compact and lightweight. However, the pneumatic driving machine suffers a problem of workability being impaired by the hose which supplies compressed air to the driving machine from the air compressor and which always accompanying the driving machine. Further, a heavy air compressor must be carried in conjunction with the pneumatic driving machine, and hence great inconvenience is encountered in moving and installing the air compressor.
For these reasons, as described in JP-A-8-205573 provided below, an electric driving machine has been proposed in place of the pneumatic driving machine, wherein a battery pack (battery) is taken as an energy source and which converts rotational energy of a flywheel rotationally driven by an electric motor into rectilinear kinetic energy used for driving a fastener. This electric driving machine accumulates rotational kinetic energy in the flywheel by driving of the electric motor; and transmits the thus-accumulated energy to a fastener driving section of a driver blade as rectilinear kinetic energy by a power transmission section including a clutch mechanism.
A clutch mechanism section in the electric driving machine usually includes a solenoid electrically connected to a battery pack by way of a semiconductor switching element (a power transistor), and is configured so as to supply an energization current to the solenoid or interrupt the supply of energization current by ON-OFF control of the semiconductor switching element. By this configuration, rotational kinetic energy accumulated in a flywheel is transmitted to a driver blade, so long as the energization current is supplied to the solenoid and the clutch mechanism is brought into an engaged state. Conversely, the rotational kinetic energy is accumulated in the flywheel as a result of an electric motor being driven by taking a battery pack as a power source, so long as the supply of the energization current to the solenoid is interrupted and the clutch mechanism section is brought into a disengaged state. At this time, startup of the electric motor is also controlled by the ON-OFF control of a semiconductor switching element (a power transistor) electrically connected between the motor and the battery pack. Meanwhile, operation of the switching element for driving a solenoid and operation of the switching element for driving a motor are controlled by a control signal output from a controller (a control circuit) including a microcomputer. The same battery pack is also used as a power source for this controller, as in the case of the motor and the solenoid. A voltage generated by lowering the voltage of the battery pack to a predetermined voltage by a power circuit (a regulator) is usually used as a power source.